Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

Advantages and disadvantages of measurement of cell mass, Define Advantages...

Define Advantages and Disadvantages of Measurement of Cell Mass? Advantage 1. It is a useful technique for estimating fungal and actinomycetes growth. Disadvantages 1.

Endoplasmic reticulum (er), Endoplasmic reticulum (ER) is the network of m...

Endoplasmic reticulum (ER) is the network of membranous tubules in the cytoplasm of a cell; involved in production of the phospholipids, proteins, and the other functions. Rough E

Which type of ecological interaction is competition, Q. What is competition...

Q. What is competition? Which type of ecological interaction is competition? The Competition is the ecological interaction in which the individuals explore the similar ecologic

State the branemark theory of osseointegration, Branemark's Theory of Osseo...

Branemark's Theory of Osseointegration In 1952, Swedish orthopedic surgeon, Branemark, conducted microscopic studies done in situ of the bone marrow in rabbit's fibula with in

Materials handling and storage, Materials Handling and Storage Materi...

Materials Handling and Storage Material handling is a very significant process in working place. The materials are handled in not finished, semi finished and finished states.

Explain transposition the great arteries with ventricular, Explain Transpos...

Explain Transposition the Great Arteries with Ventricular Scptal Defect ? Transposition of the great arteries with VSD is an indication for surgery. It is preferable to do VSD

Hydrogen bonds important for making water cohesive liquid, Hydrogen bonds a...

Hydrogen bonds are important for all of the following except:: a) Allowing carbohydrates to dissolve in water b) Stabilizing the three-dimensional shape of proteins. c) Ma

Infectious canine hepatitis, Infectious canine hepatitis The disease i...

Infectious canine hepatitis The disease is caused by type-1 canine Adenovirus in the family Adenoviridae. The disease appears in pups as peracute, acute, and mild. The clinica

Horse diseases-equine infectious anaemia, Equine infectious anaemia Eq...

Equine infectious anaemia Equine infectious anemia (EIA), an acute or chronic viral disease of the equines, shows intermittent fever, loss of weight, depression, progressive w

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd